Top 10 all-time D-line prospects

Kiper reveals his grades for top college D-linemen before they were drafted

George Gojkovich/Getty ImagesBruce Smith delivered on his tremendous potential in the NFL.

I put out my first draft guide in 1979. This year will be No. 35. That first guide was a full six years before the first NFL scouting combine. Back then, there were no online prospect guides and no recruiting rankings to track talent down to the high school level, and the draft looked something like this. For me, evaluating prospects was all about getting as much tape as I could find (there was no ESPN GamePlan), and making hundreds and hundreds of phone calls (no cellphones, either!) to coaches, scouts and front-office folks who would listen, and to evaluators at every level. You couldn't watch a verified 40-yard dash time on live TV; instead, you had to triangulate and weed out truth from fiction. It wasn't easy.

Mel Kiper's all-time draft grades

But all this time, I've kept the same 10-point grading scale, so even as the athletes changed, we can compare today where players stood among their prospect peers over a generation.

So, some parameters for what you see below:

1. The ranking is based on the final draft grade before the draft, and it goes back to 1979, my first draft guide. It's clear to me now I graded a little easier when I was younger. I didn't have the point of reference I do today.

2. The grades do not reflect NFL performance. (You'll see.) I printed these grades and simply went back through every book. I have to live with the busts.

3. There are some ties on grades, so I had to break those ties without a great deal of science. But again, I didn't break ties based on NFL production.

That said, here they are. For this group, there are great ones, but it's sad the degree to which injuries took their toll.

1. Bruce Smith, Virginia Tech (No. 1 pick, 1985)

Grade: 9.9

Well, No. 1 is a keeper. Smith finished his NFL career with exactly 200 sacks, and had 13 seasons with double-digit sacks. And this was no surprise. Smith was a relentlessly disruptive defensive player for the Hokies, and -- I love this stat -- finished his career with tackles behind the line of scrimmage that totaled more than 500 yards in losses. It was as if teams occasionally had to hand the ball off the wrong way. Smith was a big edge rusher -- he played between 265 and 280 pounds -- and had great reach and long arms at 6-foot-4, but he had a great burst and could chase you down. He could run the 40 in the 4.7-seconds range.

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